BASIC FIBROBLAST GROWTH-FACTOR EXPERIMENTALLY-INDUCED CHOROIDAL ANGIOGENESIS IN THE MINIPIG

Basic fibroblast growth factor (bFGF), a soluble mitogen, has been iso lated and purified from various organs, including the retina. In vivo angiogenic activity of bFGF has been demonstrated with several assays. An experimental model of choroidal neovascularization was developed i n the mini pig by perfusion of recombinant human bFGF through an osmot ic minipump. Endogenous bFGF and bFGF receptors were localized in the normal pig retina by immunohistochemistry and autoradiography after bi nding. The perfusion of exogenous bFGF induced well-organized new vess els along the last 3 mm of the catheter in the suprachoroidal space. T his neovascularization did not penetrate the normal Bruch's membrane. Vascular cells (identified by von Willebrand factor antibody staining) increased in number and in surface from the proximal part to the end of the intraocular catheter in all bFGF perfused eyes. In eyes perfuse d with phosphate buffered saline (controls), but not in the bFGF perfu sed eyes, an inflammatory response occurred (identified by a macrophag e specific antibody). These results demonstrate that choroidal angioge nesis can be achieved without an inflammatory response by perfusing an excess of bFGF in the suprachoroidal space.